Just read this part of the KB article:
Computers that are equipped with multiple processors that support processor power management features, such as Advanced Configuration and Power Interface (ACPI) processor performance states, require Microsoft Windows XP Service Pack 2 (SP2). Additional updates are available to optimize performance and behavior on computers that are running Windows XP SP2. Without these updates, computers that are equipped with these power management-capable, mobile, dual-core processors may experience decreased performance or unexpected behavior.
I have found this hotfix on the net, loaded it, and have seen a 12% increase in render speed on my Intel machine!!!!
Why do they hide these things from us. According to MS, the KB also mentions:
Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem
Pheww!!!!
Cheers
Jeremy

MJ Productions